Pneumatic car-buffer.



PATENTBD FEB. 7, 1905.

W. W. DENNIS.

PNEUMATIG CAR BUFFER.

APPLIOATION FILED APR. 2z. 1904.

UNITED STATES Patented February 7, 1905.

WILLIAM W. DENNIS, OF CINCINNATI, OHIO.

PNEUMATIC CAR-BUFFER.

SPECIFICATION forming part of Letters Patent No. 781,716, dated February7, 1905. Application filed April 22, 1904. Serial No. 204,389.

To /tZ/ whom it may concern:

Beit known that I, WILLIAM W. DENNIS, a citizen of the United States,residing at East Norwood, Cincinnati, in the county of Hamilton andState of Ohio, have invented certain new and useful Improvements inPneumatic Car-Buffers, of which the following is a specification.

This invention provides a special construction of buffer for useparticularly on railwaycars or in similar adaptations for absorbing andreducing the vibration, shock, or jar consequent to the starting andstopping of a train and caused by bu mping of the cars one against theother.

The buffer consists, preferably, of pneumatic cushion means coperatingwith a piston or the like which carries the coupling devices ltoazcolnplish the desired results above outine For a full description ofthe invention and the merits thereof and also to acquire a knowld edgeof the details of construction of the means for effecting the resultreference is to be had tothe following description and accompanyingdrawings.

While the essential and characteristic features ofthe invention aresusceptible of modiiication, still the preferred embodiment of theinvention is illustrated in the accompanying drawings, in which- Figure1 is a side elevation of a buffer embodying my invention. Fig. 2 is abroken view showing more clearly the arrangement of the inlet and outletpipes leading into the cylinder, said view being partially in section.Fig. 3 isa vertical sectional view showing more clearly the constructionof the puppet-valve carried by the secondary air-pipe whichcornrnunicates with the cylinder. Fig. 4 is a view similar to Fig. 3,showing the somewhat-modified construction of puppet-valve utilized togovern the outlet by which the air in the cylinder is permitted to passtherefrom. Fig. 5 is a transverse sectional View, partially broken away,taken about on a line 5 5 of Fig. 3.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the drawings by the samereference characters.

Generally describing my invention, the same consists of an air-cylinder1, which is suitably mounted upon the under side of a car-body 2, inwhich is located the piston 3. Air is admitted into the cylinder 1through a `main supply-pipe 4, which leads from a suitablecompnessed-air reservoir, and the amount of air admitted into thecylinder is controlled by suitable valve means adapted to be operatedbytheengineerofthetrain. Themainsupplypipe 4 leads into the cylinder ata suitable point between the ends of the latter, and a checkvalve isdisposed in the length of the pipe 4 at a point adjacent the cylinder 1aforesaid. My invention embodies also a peculiar arrangement ofair-pipes by which the air is admitted into and conducted from thecylinder l and peculiar valve means for governing the admission andoutflow of the air in a manner which will be described more fullyhereinafter.

It is designed to utilize any suitable form of coupler in connectionwith my buffer, and this coupler (designated 5 in the drawings) ispreferably carried by the piston-rod 6 of the piston 3, so thatin thebumping of the cars as the train starts and stops the jar received bythe coupling means will be directly taken up by means of my pneumaticbuffer. The secondary air-pipe 7 is mounted upon the cylinder, beingprovided with a branch outlet-pipe 7a and a branch inlet-pipe 7b. VThepipe 7 is merely a conducting-pipe through which the air which has beenadmitted into the cylinder 1 through the main supply-pipe 4 may passfrom one end of the cylinder to the other end thereof, or, in otherwords, from one side of the piston 3 to the other side thereof. Apuppet-valve 8 is disposed in the length of the branch pipe 7", itsvalve-plug 8*x being mounted in a casing 9 and normally remaining seatedagainst a valve-seat 10, provided in said casing. The valve 8 isnormally held closed,so as to prevent the air admitted into the cylinder1 from escaping therefrom until this is compressed to such an extent asto cause automatic opening of the valve 8, andthe compression of the airin the cylinder, which causes opening Aof the valve 8, is of course dueto the butiing movement of the piston 3. Projected from IOO thevalve-plug 88L are guide-rods 11, which latter are rigidly mounted uponthe said plug, being adapted to carry an adjustable plate 12. A springis interposed between the plate 12 and the valve-plug 8, and this springnormally tends to hold the valve closed until the tension thereof hasbeen overcome due to increase in pressure of the air within the cylinder1 as caused by movement of the piston 3. The supporting-plate 12 is heldrigidly at an ascertainedI adjustment by means of an adjusting member13, the latter being a screw member of any suitable type. Thesupporting-plate 12 is prevented from displacement from the guide-rods11 by heads 14, provided upon said rods 11. Owing to the adjustabilityof the tension of the spring 15, it will be noted that the valve 8 maybe caused to unseat at different degrees of pressure ofthe air withinthe cylinder 1, so as to admit of outflow of this air through thesecondary air-pipe 7 and back into the cylinder through the branch pipe7". A check-'valve 16 is carried by the secondary air -pipe 7, so as toprevent backdescribed.

ilow of the air in the cylinder 1 through the said secondary pipe 7. Anoutlet-pipe 17 leads from the end of the cylinder 1 opposite to thatadjacent which the outlet branch pipe 7FL is located, and a puppet-valve18 governs the egress of the air from the cylinder 1 through the pipe17. The puppet-valve 18 is of a form similar to the valve 8, beforedescribed, also having a valve-plug 8a mounted in a valve-casing 9 andprovided with guiderods 11. This valve -is spring-operated and is'adapted to open at varied heights in the pressure of the air within thecylinder 1 by means of adjustment of the spring 15 adjacent thereto,which spring is operated upon by members 12 and-13, which havebeen'before The air, however, which passes the puppet-valve 18 escapesfrom the valvecasing 9 thereof through outlet-openings 19 in the lowerend ofsaid casing. The adjustable members 13, /which cooperate with thetension-adjustingplates 12, are mounted in tubular members 20, suitablydisposed at the lower portions of thevalve-casings 9, as shown in Figs.4 and 5, and ready access may be had .for adjustment of the, member 13,which cooperates with the puppet-'valve 8, by removal of fa' screw-cap21, which normally houses the said member. The adjusting members 13 areprovided with finger-pieces 22l at. their lower ends, by which saidmembers may be properly manipulated. The adjusting member 13 of thepuppet-valve 18 has its lower end exposed and not housed by any parts asdescribed with reference to the adjusting member 13 of the puppet-valve`8.

1n the practical operation of my invention preparatory to stopping thetrain the engineer or other operatoryas the case may be, by operation ofproper mechanism admits air into the cylinder -1 through the mainsupplypipe 4, this air passing into the' end of the cylinder designatedb, as illustrated in the drawings. The air cannot pass back through thesupply-pipe 4 owing to the operation ot' a suitable check-valve 23, andit may be here said that it is designed to utilize any suitable form ofcheck-valve in connection with my invention. As the tra-in slackens inspeed the bumping movement of the cars causes actuation of the pistontoward one end ot' the cylinder-namely, that indicated by the letterband the airin the cylinder forms a cushion for the piston in a'mannerwhich will be readily comprehended. As the piston 3 is gradually. forcedtoward the end b of the cylinder 1 in the above movement the air in thepiston is compressed until the pressure thereof causes the puppet-valve8 to open, thereby admitting of passage of this air through thesecondary air-pipe 7 in the other end of the cylinder, which forpurposes of this description is indicated at a. The airwhich passes thepuppet-valve v8 into the end a of the cylinder is prevented from passingback from the. secondary air-pipe 7 by the checkvalve 16 adjacent thebranch inlet-pipe 7b. When the piston 3 nears the end b ofthe cylinder1, same closes the outlet-pipe 7 when said piston reaches an ascertainedpoint in its movement, a suiiicient amount of air remaining in the end bof the cylinder, however, to form an eicient cushion therefor to receivethe jar of the sudden stopping ofthe train.

As the train starts, the piston 3 begins to move, because of the couplerconnections with the piston-rod 6, toward the end a of the cylinder 1,gradually compressing the air in this end of the cylinder. When thepressure of the air in the end a of the cylinder 1 reaches anascertained height in the starting movement of the train` thepuppet-valve 18 opens so as to gradually admit of ,escape of the airfrom the cylinder through the outlet-pipe 17 and openings 19. When thepiston rin its last-described movement reaches a point adjacent the enda of the easing, so as to close the entrance to the outlet-pipe 17 theremaining air is prevented from passing olf through this pipe 17 andconstitutes acushion or buffer, as will be readily seen.

In order to limit the movement-of the piston and prevent likelihoodolsthe shock of the cars being received by the cylinder-heads of vthecylinder 1, the pistoni-rod 6 is provided in its length with stopmembers in the formof anges 24, andthese members cooperate with a 'rigidhanger 25 to limit the longitudinal movement of the piston 3 and preventcontact of this piston with the. heads ofthe cylinder 1, abovementioned. 1n order to prevent turning movement of `the coupler 5, thepistonrod 6 is preferably squared in its length, passing through asquared opening in the hanger IOO IIS

25. The coupler 5 of one car is thus always held in a position ready toengage the coupler carried by the other car. It is designed that a ltion of a cylinder, a piston movable in said single pneumatic buffer beused at one end of each lar, and the buffer, as above set forth,efi'ectually absorbs the motion and deadens the shock arising, thuslengthening the life of the cars, as well as the couplers used thereon.The

cylinder, a piston-rod, a coupler mounted on said piston-rod, a mainsupply-pipe leading' length of the stroke of the piston would not bemuch, but will be varied somewhat found best, and the amount of airalways coniined in the cylinder will of course be determined by thedistance between the ends of the cylinder, and the outlet-pipes 7"l and17 will lead therefrom.

Having thus -described the invention, what is claimed as new is- 1. In apneumatic. ear-buffer, the combination of a cylinder, a piston operatingin said cylinder, a piston-rod adapted to reeeivea buffingl shock, amain supply-pipe leading into the cylinder, a secondary pipe leadingfrom a point adjacent one end of the cylinder into the cylinder at apoint adjacent the opposite end thereof, a puppet-valve controlling thepassage of a pressure medium through the secondary pipe aforesaid, and asecond puppetvalve governing the escape of the pressure medium from thecylinder.

2. ln a pneumatic car-buffer, the combination of a cylinder, a pistonmovable therein, a piston-rod, a coupling or buliing member carried bysaid piston-rod, a main pipe for supplying a pressure medium to thecylinder, a secondary pipe or passage-way for conducting the pressuremedium from one side of the piston to the other, and valve meansgoverning the outiiow of the pressure medium from the cylinder.

3. In a pneumatic car-buffer, the combination ofa cylinder, a piston, apiston-rod,acoup lingor builingmember disposed upon said rod, a mainsupply-pipe for conveying a pressure medium into the cylinder, asecondary' pipe for conducting' the pressure medium from one side of thepiston to the other, puppet and check valves in the length of thesecondary pipe aforesaid, an outlet-pipe leading from the cylin( ler,andvalve means governing egress of the pressure medium through theoutletpipe.

-L ln a pneumatic car-buffer, the combination of a cylinder, a pistonmovable therein, a piston-rod extending from the piston and carrying' acar-coupler or similar parts, a main supply-pipe for conductingapressure medium into the cylinder, a,secondary pipe having outlet andinlet branches communicating with the cylinder, a puppet-valve governingthe passage of the pressure medium through the outlet branch of thesecondary pipe aforesaid, a check-valve disposed in the length of saidsecondary pipe, an outlet-pipe leading from the cylinder, and apuppet-valve governing the outliow of the pressure medium through theoutlet-pipe aforesaid.

5. In a pneumatic car-buffer, the combinainto the cylinder at a pointbetween the ends thereof, a secondary pipe having outlet and inlet pipesleading' into the cylinder, a puppet-valve governing the outlet of thepressure medium through the outlet-pipe of the secondary pipe aforesaid,a check-valve carried by the secondary pipe, an outlet-pipe to admit ofescape of the pressure medium from the cylinder, and valve meansgoverning the egress of the pressure medium through the outlet-pipeaforesaid.

6. In a 'pneumatic car-buffer, the combination of a cylinder, a pistonmovable therein, a piston-rod, a coupler carried by the pistonrod, amain supply-pipe having a pressure medium leading into the cylinder at apoint between the ends thereof, a secondary pipe provided with a branchoutlet-pipe leading' into the cylinder adjacent one end thereof andhaving an inlet-pipe leading into the cylinder valve disposed in thelength of the branch outlet-pipe, a check-valve carried by the secondarypipe, and an outlet-pipe leading from the end of the cylinder oppositethat adjacent which the branch outlet-pipe aforesaid is disposed.

7. In a pneumatic car-buffer, the combination of a cylinder, a pistondisposed in said cylinder, means for supplying'a pressure medium to thecylinder, means for conducting' the pressure medium from one end of thecylinder to the other and from one side of the piston to the other, apiston-rod carried by the piston, and means for limiting' the movementof the piston-rod independently of the cylinder.

8. In a pneumatic car-buffer, the combination of a cylinder, a. pistondisposed in said cylinder, means for supplying' a pressure medium to thecylinder, means for conducting' the pressure medium from one end of thecylinder to the other and from one side of the piston to the other. apiston-rod carried by the piston, and stop means carried by thepiston-rod and limiting the movement thereof.

9. In a pneumatic car-buffer, the combination of a cylinder, a pistondisposed in said cylinder, means for supplying a pressure medium to thecylinder, means for'conducting' the pressure medium from one end of thecylinder to the other and from one side of the piston to the other, apiston-rod carried by the piston, and stop members projected from thepiston-rod and adapted to limit the movement yof the said piston-rod.

10. 1n a pneumatic car-buffer, the combination of a support, a cylinder,a piston mounted in said cylinder, a piston-rod, a coupler disposed uponthe piston-rod, means for supplying' a pressure medium to the cylinder,means for governing the outow of the pressure rne- IOO ISO

dium from the Cylinder, a rigid hanger carried i medium from thecylinder, spring means for bythe support aforesaid, and stopmembersnormally holding the puppet-valves closed, projected from the piston-rodand Cooperating means for adjusting the tension of the spring with saidrigid hanger to limit the movement and means aforesaid for the purposeset forth. I5

of the piston-rod and piston. In testimony whereof Iaix mysignature inl1. In apneumatic car-buffer, the oolnbinapresence of two witnesses.

tion of a cylinder, a piston movable therein,i ,ILLIAM W. DENNIS YL SJ apiston-rod, a oouplmg or bung memhel carried by the piston-rod, meansfor supply- Witnesses:

ing a pressure medium to the cylinder, pup- ORA B. KIBBY,

pet-valves governing the egress of the pressure i HoM ER HENDRIXsoN.

